U.S. patent number 5,839,186 [Application Number 08/480,153] was granted by the patent office on 1998-11-24 for component attracted state detecting system for component mounting machine.
This patent grant is currently assigned to Yamaha Hatsudoki Kabushiki Kaisha. Invention is credited to Hitoshi Onodera.
United States Patent |
5,839,186 |
Onodera |
November 24, 1998 |
Component attracted state detecting system for component mounting
machine
Abstract
A method and apparatus of mounting components and recognizing
two different types of components, one by a photographic
recognition practice and the other by an optical recognition
practice. At least two pick-up devices are carried by a mounting
head and a light source and background device is moveable supported
by the mounting head into a first position wherein a photographic
recognition method can be practiced on a component mounted on one
of the pick-up devices, a second position wherein one or both of
the pick-up devices may hold components for recognition by the
optical device and a third position where a camera carried by the
mounting head can be employed for recognizing a substrate. The
control routines for each type of sensing operation are
disclosed.
Inventors: |
Onodera; Hitoshi (Iwata,
JP) |
Assignee: |
Yamaha Hatsudoki Kabushiki
Kaisha (Iwata, JP)
|
Family
ID: |
17829452 |
Appl.
No.: |
08/480,153 |
Filed: |
June 7, 1995 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
148832 |
Nov 5, 1993 |
|
|
|
|
Foreign Application Priority Data
|
|
|
|
|
Nov 5, 1992 [JP] |
|
|
4-296124 |
|
Current U.S.
Class: |
29/720 |
Current CPC
Class: |
H05K
13/0812 (20180801); Y10T 29/53087 (20150115) |
Current International
Class: |
H05K
13/04 (20060101); H05K 13/08 (20060101); H05K
13/00 (20060101); B23P 021/00 () |
Field of
Search: |
;29/720,740,741,742,721
;356/375 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
0471272 |
|
Feb 1992 |
|
EP |
|
236598 |
|
Feb 1990 |
|
JP |
|
3110896 |
|
May 1991 |
|
JP |
|
3218697 |
|
Sep 1991 |
|
JP |
|
513991 |
|
Jan 1993 |
|
JP |
|
6152194 |
|
May 1994 |
|
JP |
|
9214988 |
|
Sep 1992 |
|
WO |
|
Primary Examiner: Hall; Carl E.
Assistant Examiner: Goins; Christopher
Attorney, Agent or Firm: Knobbe, Martens, Olsen & Bear
LLP
Parent Case Text
This application is a divisional of U.S. patent application Ser.
No. 08/148,832, filed Nov. 5, 1993 abandoned.
Claims
I claim:
1. A component handling device for providing photographic
recognition of a component comprised of a head supported for
movement in X and Y directions, a pick-up device carried by said
head for picking up a component, a combined light source and
diffuser plate for emitting and diffusing light toward a camera
carried by said head, said combined light source and diffuser plate
having an opening extending therethrough for passing light to a
lens of said camera, means for supporting said combined light
source and diffuser plate for relative movement to said head
between a first operative position in confronting relationship to
said camera, a retracted position and a second operative position,
and another camera cooperative with said combined light source and
diffuser plate when in said second operative position, said head
being moveable relative to said other camera, said other camera
cooperating with an article carried by said pick-up device.
2. A component handling device for providing photographic
recognition of a component as set forth in claim 1 wherein the
pick-up device extends through the hole in the combined light
source and diffuser plate when cooperating with the other
camera.
3. A component handling device for providing photographic
recognition of a component as set forth in claim 2 wherein there
are two pick-up devices supported by the head.
4. A component handling device for providing photographic
recognition of a component as set forth in claim 3 wherein the
combined light source and diffuser plate cooperates with only one
of the pick-up devices.
5. A component handling device for providing photographic
recognition of a component as set forth in claim 4 further
including a sensor carried by the head for sensing components
carried by the two pick-up devices.
6. A component handling device for providing photographic
recognition of a component comprised of a camera, a head supported
for movement in X and Y directions relative to said camera, a
pick-up device carried by said head and adapted to pick up a
component to be photographed by said camera, and means for
supporting said combined light source and diffuser plate by said
head and for relative movement to said head between an operative
position in confronting relationship to said camera and a retracted
position that does not confront said camera.
7. A component handling device for providing photographic
recognition of a component as set forth in claim 6 wherein the
combined light source and diffuser plate has an aperture therein
for passing the pick-up device.
8. A component handling device for providing photographic
recognition of a component as set forth in claim 7 further
including a sensor carried by the head for sensing a component
carried by the pick-up device.
9. A component handling device for providing photographic
recognition of a component as set forth in claim 8 wherein there
are two pick-up devices carried by the head.
10. A component handling device for providing photographic
recognition of a component as set forth in claim 9 wherein the
sensor cooperates with both of the pick-up devices to sense
simultaneously components carried thereby.
Description
BACKGROUND OF THE INVENTION
This invention relates to a component attracting state detecting
system for a component mounting machine and more particularly to an
improved apparatus for handling a wide variety of components,
detecting their orientation, and mounting them as well as
recognizing the substrate upon which they are mounted.
A wide variety of apparatus have been proposed for picking up small
discreet components at a pick up station and mounting them on a
substrate at an accurate location. Such apparatus are used, for
example, in mounting such small components as integrated circuits,
resistors, capacitors and like objects on a printed circuit board.
The components are normally presented at the pick up stations in
feed tapes which are incrementally advanced and from which pick up
heads select the components and move them to their mounting
position.
By the very nature of this type of apparatus, the component pick-up
device is not able to pick up the component at an exact location
because some latitude must be permitted in cavity in the tape so as
to permit the component to be easily withdrawn. Therefore, it has
been the practice to provide an arrangement for detecting the
condition of the component picked-up by the pick-up device so as to
make corrections in the mounting location to correspond for the
offset of the pick up. For example, if a component is picked up and
translated in an X--X and Y--Y direction for mounting, the
components offsetting of the pick up location relative to the
pick-up device in the X--X and Y--Y axes can affect where the
component should be mounted. Said another way, the pick up device
must be positioned somewhat differently to correspond to these
offsets. In addition, there may be rotational offset of the
component relative to the axis of the pick-up device and this also
must be compensated for.
A wide variety of recognition apparatus have been proposed for
determining the corrective factors from the offset of the component
relative to the pick-up device. An optical method and apparatus for
performing such a recognition and measurement is disclosed in the
co-pending United States Patent application of Hiroshi Sakurai et
al entitled "Method For Mounting Components And An Apparatus
Therefor", Ser. No. 08/073,741, filed Jun. 8, 1993 and assigned to
the Assignee hereof. That apparatus employs a laser light source
which emits a plurality of parallel light rays across an area into
which the component is positioned. The component then casts a
shadow on a photo sensitive detector such as a capacitor coupled
device(C.C.D.). The component is rotated and from the rotational
measurements, the corrective factors can be readily determined in
the method as described in that application, the disclosure of
which is incorporated herein by reference.
That method and apparatus, however, is primarily applicable to
components having regular shapes such as rectangular shapes and
components which do not have irregularities such as are presented
by mounting pins, extending lead wires or the like.
Another type of detecting device employs a photographic method
wherein the underside of the component (the side to be mounted on
the substrate) is photographically recognized and from the
photographic recognition, not only the type of component but
misalignments in its pick up location can also be determined.
Since the aforenoted measurements are normally performed by
different types of apparatus, many mounting devices are not capable
of mounting both types of components or if they are, they must
provide separate mounting heads and sensing devices for each type
of component.
It is, therefore, a principal object to this invention to provide
an improved mounting and orientation determination apparatus that
is useable with a wide variety of types of components.
It is a further object to this invention to provide a mounting and
orientation handling device that is capable of handling different
components and recognizing the components by two different types of
recognition apparatus while using a single mounting head.
With the photographic recognition method it is desirable to provide
not only a light source so that the component will be adequately
illuminated for photographic purposes, but also a background which
will black out or obscure the pick-up device and other components
from the field of view of the camera. The previous types of devices
proposed for this purpose have, however, limited the applicability
of device from handling a wide variety of components and also have
been somewhat cumbersome and complicated.
It is, therefore, a still further object to this invention to
provide an improved combined light source, diffuser plate and
background for use in a component handling device which can be
moved to a position behind the component when photographed by a
camera and may be moved out of the way when not required.
As has been noted, it is desirable if a single mounting head is
capable of handling components which can be recognized by either of
the aforenoted methods. In fact, it is desirable to also provide an
arrangement wherein some of the recognition methods may be
performed on plural components at the same time and in a common
sensing station. However, if this is done with the optical
recognition method, which lends itself to such multiple sensing,
then it is difficult to provide the light source and background
required for the photographic recognition method.
It is, therefore, a still further object to this invention to
provide an improved mounting apparatus for components employing
plurality of pick devices and which will accommodate either type of
recognition method.
It is a further object to this invention to provide an improved
component mounting device that employs plural pick-up devices and
which can incorporate a light and background arrangement for
assisting in photographic recognition without interfering other
methods of recognition or the picking up and sensing of plural
components by these other methods.
As should be readily apparent from the foregoing description, the
use of a moveable light source and background device on a mounting
head has a number of advantages for recognition of components
picked up by the pick-up devices carried by the head. However, it
is also desirable, at times, to have a sensing device on the
mounting head which can sense the substrate and recognize it onto
which the components are being mounted. Where the mounting head
includes a light source, it is desirable if that light source can
also be used in the substrate recognition system.
It is, therefore, a still further object to this invention to
provide an improved apparatus have a mounting head for handling
components to be positioned on a substrate, a photo assist device
for assisting in photographic recognition of those articles and
also a photograph recognition device carried by the mounting head
for recognizing the substrate and which can use the same photo
assist device in this operation.
SUMMARY OF THE INVENTION
A first feature of this invention is adapted to be embodied in a
component mounting device for picking up a component and mounting
the component in precise locations on a substrate. The apparatus
comprises a pick-up device for picking and depositing components
and means which support the pick-up device for movement between a
pick up position for picking up any of a plurality of components
and a deposit position for depositing the components. A first
recognition device is co-operable with the pick-up device and a
first type of component carried thereby for providing data to
detect the orientation of the first type of component as held by
the pick-up device in a first manner. A second recognition device
is co-operable with the pick-up device and another type of
component carried thereby to detect the orientation of the other
type of component as held by the pick-up device in a second manner
which is different from the first recognition manner.
Another feature of the invention is adapted to be embodied in a
component handling device for photographic recognition of a
component comprised of a head and a combined light source and
diffuser plate for emitting and diffusing light toward a camera.
Means support the combined light source and diffuser plate for
movement relative to the head between an operative position in
confronting relation to the camera and a retracted position.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plane view of a component mounting and detecting
apparatus constructed in accordance with an embodiment of the
invention.
FIG. 2 is a front elevational view thereof.
FIG. 3 is an enlarged front elevational view of the mounting
nozzles and detecting head in a first position.
FIG. 4 is an enlarged view, in part similar to FIG. 3, and shows
the construction when the photographic recognition technique is
being employed.
FIG. 5 is a top plan view of the apparatus in the condition as
shown in FIG. 4.
FIG. 6 is an enlarged view, in part similar to FIGS. 3 and 4, and
shows the apparatus when a pair of components are being detected in
the optical detecting section.
FIG. 7 is a top plan view of the apparatus as shown in FIG. 6.
FIG. 8 is an enlarged elevation view, in part similar to FIGS. 3, 4
and 6, and shows the apparatus when the substrate is being
photographically scanned.
FIG. 9 is a top plan view of the apparatus shown in the condition
of FIG. 8.
FIG. 10 is a block diagram showing the interrelationship of the
components of the system.
FIG. 11 is a block diagram showing the control routine when a
component is being attracted and mounted using the photographic
recognition technique.
FIG. 12 is a block diagram showing the control routine when a
component is being mounted using the optical detecting
technique.
FIG. 13 is a block diagram showing the routine when the substrate
is being recognized photographically.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE
INVENTION
Referring now in detail to the drawings and initially to FIGS. 1
and 2, a component mounting apparatus constructed and operated in
accordance with a preferred embodiment of the invention is
identified generally by the reference numeral 21. The apparatus 21
is adapted to mount small components such as integrated circuits,
resistors, capacitors or the like which are supplied at respective
delivery stations 22 and 23 disposed on opposite sides of a
conveyor assembly 24. The delivery sections 22 and 23 comprise a
plurality of individual feeders 25 and 26, respectively, of the
type each of which comprises a roll of tape having pockets in which
the components to be mounted are contained. These tapes are
advanced by a ratchet mechanism under a control as is well
known.
The conveyor 24 selectively presents substrates, indicated at 27,
to a mounting area positioned between the delivery sections 22 and
23. A pick-up and recognition device, indicated generally by the
reference numeral 28 is mounted for movement in an X--X and Y--Y
direction in a manner which will be described so as to selectively
pick up components from the feeders 25 and 26 and position them on
the substrates 27 at the desired and pre-programmed location. In
addition, the pick-up and recognition station 28 cooperates so as
to provide an indication of the orientation of the components
picked up thereby so as to adjust for their mounting position, as
will be described.
The pick-up and recognition station 28 includes a mounting head 29
which is mounted for movement along a carriage 31 by means of guide
rails 32 and a driving feed screw 33. The feed screw 33 has a ball
nut connection with the mounting head 29 so that upon rotation of
the feed screw 33, the mounting head 29 will move in the X--X
axis.
An X--X axis drive motor 34 is mounted at one end of the carriage
31 and is coupled to the feed screw 33 for driving it in clockwise
or counter-clockwise directions so as to appropriate position the
mounting head 29. An encoder 35 is coupled to the electric motor 34
and provides a positional X--X signal to the control apparatus as
shown in the block diagram of FIG. 10.
The carriage 31 is mounted for movement in the Y--Y direction on a
pair of guide rails 36 which are disposed at opposite sides of the
area where the substrates or printed circuit boards 27 are disposed
and outwardly of the ends of the feeder sections 22 and 23. A
suitable way construction permits this movements along the guide
rails 36.
The carriage 31 is provided with a recirculating ball nut 37 which
is engaged with a feed screw 38 that is journalled on one of the
guide rails 36. This feed screw 38 is driven by a reversible
electric motor 39 so as to move the carriage 31 and mounting head
assembly 28 in the Y--Y direction. An encoder 41 is coupled to the
motor 39 and as shown in FIG. 10, provides an output signal
indicative of the Y--Y position of the mounting head assembly
28.
The entire assembly as thus far described may be mounted
conveniently on a table 42 so that the apparatus can be moved from
location to location, but also can be retained in position.
The construction of the gripping and detecting section 28 will now
be made by reference to FIGS. 3 through 9. Referring first to FIG.
3, it should be noted that the mounting head 29 carries, in this
embodiment, two pick-up nozzles indicated by the reference numerals
43 and 44. The pick-up nozzles 43 and 44 are of the vacuum type,
but it should be readily apparent to those skilled in the art how
the invention can be employed with other types of pick-up nozzles.
Reference is made to the co-pending application filed in the name
of Hiroshi Sakurai etal entitled "Method For Mounting Components
And An Apparatus Therefor", Ser. No. 08/086,512, filed Jul. 1,
1993, and assigned to the Assignee hereof for a more detailed
description of how the plural pick-up nozzles may be mounted on a
single mounting head. The disclosure of that application is
incorporated herein by reference.
Briefly summarized, each of the pick-up nozzles 43 and 44 is
mounted for movement in a vertical direction along a Z--Z plane by
the mounting head 29 and is driven for movement in such direction
by a respective Z--Z axis servo motor 45 or 46. Encoders 47 and 48
are coupled to the drive motors 45 and 46 so as to provide an
output signal indicative of the ZZ position of the respective
nozzles 43 and 44 as shown in FIG. 10.
In addition, the nozzles 43 and 44 are also supported for rotation
about vertical R axes in a manner described in the aforenoted
co-pending application Ser. No. 08/086,512. Rotational movement
about these axes is obtained by R axis servo motors 49 and 51 which
are coupled to the nozzles 43 and 44, respectively, for effecting
rotary movement. Encoders 52 and 53 are connected to the motors 49
and 51, respectively, and provide output signals indicative of the
angular position about the rotation R axes. Again, the relationship
of these components is shown in FIG. 10.
In accordance with an important feature of the invention, the
station 28 also serves for providing detection of the position of
the components which are picked up by the pick-up nozzles 43 and 44
so as to make correction factors for misalignment of their pick up
from the ideal position so that when they are; positioned on the
substrate 27 they will be positioned in an accurate location.
In accordance with this invention, two different forms of detectors
are employed depending upon the type of article which will be
picked up by the nozzles 43 and 44. If the article to be picked up
has a generally regular rectangular configuration, such as many
chips and other components, then the orientation will be detected
by a detector, indicated generally by the reference numeral 54,
which is described as being of the optical type. This is the type
of detector which is described in detail in aforenoted co-pending
application Ser. Nos. 73,741, and 86,512, the disclosures which
have already been incorporated herein by reference.
Briefly, this detector 54 includes a laser light source 55 that
emits generally straight light rays across a gap 56 in which the
pick-up nozzles 43 and 44 may be positioned, as will be described,
and cast shadows on a receptor 57 of the capicator coupled type
(C.C.D.) type. In order to permit simultaneous recognition and
measurement of components carried by both of the pick-up nozzles 43
and 44 at the same time, these nozzles are staggered relative to
the gap 56 as best seen in FIGS. 6 and 7 and this method of
simultaneous measurement is as described in any of the routines of
application Ser. No. 86,512.
In addition to the optical detecting method described in the
aforenoted co-pending applications, at least one of the pick-up
nozzles 43 and 44 and in this case the pick-up nozzle 43, is
adapted to present components to a further type of detector, a
photographic detector, indicated at the reference numeral 58 in
FIG. 1 and which is positioned at one side of the conveyor 24. When
this detector 58 is employed, the head assembly 28 is moved into
registry with it so that the component carried by the nozzle 43 can
be read, in a manner which will be described.
To facilitate this reading, there is provided an optical assist
device, indicated generally by the reference numeral 59 which is
mounted on the head 29 in a manner for movement in a direction
parallel to the upper surface of the optical detector 54. This
optical assist device 59 is comprised of a light source 61 of a
suitable type such as an array of light emitting diodes and a lower
diffuser section 62 which also forms a background for photography
which will transmit and diffuse the light. The diffuser section 62
may be comprised of a milk white acrylic plate or the like so that
light from the emitter 61 will be diffused. The light source 61 and
diffuser plate 62 are provided with an aperture 63 which, when
brought in registry with the nozzle 43, will act as a background
for photographing of a component carried by this nozzle 43 by the
photographic detection section 58 for recognition and orientation
calculation purposes.
As has been noted, the photo assist section 59 is supported for
transverse movement and this transverse movement is accomplished by
means of a driving mechanism, indicated generally by the reference
numeral 64 and which is comprised of a first hydraulic or pneumatic
cylinder 65 that has an actuating rod 66 that passes through a
mounting member 67 which is affixed to and carries the photographic
assist mechanism 59 including the light source 61 and diffuser
plate 62. The piston rod 66 has a portion 68 that extends through
an abutment member 69 fixed to one end of the mounting member 67
and which is urged normally into engagement with an end of the rod
66 by a coil compression spring 71 loaded between the abutment
member 69 and an enlarged end 72 of the piston rod 66. Hence, when
the cylinder 65 is actuated to move the piston rod 66 to the left
as shown in the figures, the photo assist device 59 will be moved
in the same direction.
The actuating mechanism 64 further includes a second cylinder
assembly 73 that has a piston rod 74 that is connected to an
abutment member 75. When the piston rod 74 is extended, the
abutment member 75 will contact the abutment member 69 and effect
limited movement of the light assist device 59 in a manner as will
be described.
The detecting and mounting head 28 also includes a further camera
type detector 76 which has its lens disposed above one side of the
gap 56 so that when the mounting head 28 is positioned above a
substrate or circuit board 27 on the conveyor 24, a portion of it
can be optically viewed and photographed. The photo assist device
59 is adapted to assist in this operation in a manner which will
become apparent shortly.
FIG. 3 illustrates the pick-up head 28 in a position wherein the
nozzles 43 and 44 may either or both be used to pick up components
from the feed sections 22 and 23 and to place those components on
the substrate or printed circuit board 27. In this position,
neither of the fluid motors 65 nor 73 are actuated and the photo
assistance device 59 is retracted to an extreme right hand first
position as shown in FIG. 3. It should be noted that this device
carries three limit stops 77 which indicated each of the three
positions of the photo assist device 59 in conjunction with a
detector 78 actuated by the limit stops 77.
FIGS. 4 and 5 show the mechanism in a position wherein the
photographic detecting section 58 of the apparatus is employed. In
this condition, the nozzle 44 is fully retracted and, before the
nozzle 43 is lowered, the fluid motor 65 is actuated so as to move
the photo assist device 59 to the position wherein the opening 63
registers with the nozzle 43. The nozzle 43 may then be lowered to
a position where it will extend through the opening 63. The light
source 61 can then be illuminated and the diffuser 62 will permit
the light to pass down sufficiently to photograph a component
C.sub.1 picked up by the nozzle 43 at the photographic detector
section 58.
In this condition, the photographic detector section 58 can compare
the image with a memory and determine the actual location which the
component C.sub.1 has been picked up so that appropriate
orientation can be made in a manner which will be described. The
type of component C.sub.1 that cannot be recognized by the light
sensing device 54 is a type of component which may have a number of
pins on its lower surface or may have other characteristics that
make the light source detection not acceptable.
FIGS. 6 and 7 show the apparatus in a condition corresponding to
that of FIG. 3, but in this view there are shown components C.sub.2
picked up by each of the nozzles 43 and 44 and positioned in the
optical detector section 54 for light detection of the orientation
of the component C.sub.2 relative to the pick-up nozzles 43 and 44,
respectively, in accordance with any of the methods as described in
co-pending application Ser. No. 86,512. Since that disclosure has
been incorporated herein by reference, the description of
performing that detection method will not be repeated.
The remaining possible mode of operation is depicted in FIGS. 8 and
9 and this is the mode when the camera 76 carried by the head
assembly 28 is employed for photographing and recognizing a
substrate 27 on the conveyor 24. In this condition, the drive
cylinder 65 for the photographic assist device 59 is not actuated,
but the drive cylinder 73 is. This causes the piston rod 74 to
extend and engage the abutment 75 and abutment member 69 and urge
them to the left so as to compress the coil compression spring 71.
This causes the carrier 67, light source 61 and diffuser plate 52
to be moved to their third position wherein the aperture 63 is
aligned with the recess 56 in the optical sensor section 59. Hence,
the field of view of the camera 76 is the unobstructed and the
substrate 27 can easily be photographed. The light from the light
source 61 is illuminated at that time and diffused by the diffuser
plate 62 so as to assist in the photographic recognition of the
substrate 27.
The mode of operation of the total apparatus will now be described
and initially reference will be made to FIG. 10 which shows the
interrelationship of the various components thus far described and
additional components which will now be described.
The optical detector unit 54 outputs its information to a laser
unit processor 79 which is mounted on the mounting and detecting
head 28 and outputs its signals to a main controller,indicated. in
block form by the reference numeral 81. This signal is received by
an input/output means 82 of the main controller. The output of the
position detecting means 78 which detects, as aforenoted, the
position of the optical assistance unit 59 is also outputted to the
input/output means.
The drive assembly 64 of the photo assisting means 59 is controlled
by the output of the input/output means 82 as is the operation of
the light emitter 61 thereof.
The main controller 68 also has an image processing section 83
which receives signals from both the substrate camera 76 and the
component recognizing camera 58 and contains a memory that will
provide recognition of both the substrate and the component picked
up by the pick-up nozzle 43 and provides information to a main
processor 84 which, in turn, calculates the corrective factors to
be applied. The main processor also is interrelated to an axis
controlled driver stage 85 which receives signals from the various
position detectors such as the R axis position detectors 52 and 53
of the pick-up nozzles 43 and 44 respectively and the Z axis
position detectors 47 and 48 associated with the nozzles 43 and 44.
In addition, the X and Y axis position detectors 34 and 41 output
their signals to the axis driver controller 85 which then sends
signals to the respective servo motors, 35, 39, 49, 51, 45 and 46
for appropriately positioning the components in accordance with the
type of control routine which will be accomplished. A portion of
these control routines will now be described by reference to FIGS.
11 through 13.
In describing each of the sequences of operation, the actual way in
which the main controller 81 operates to control the axis driver
controller 85 and the X axis servo motor 35 and Y axis servo motor
39 to move the pick-up head 28 into registry with the appropriate
feeder 25 or 26 in the feeder stations 22 and 23 may be of any
conventional system. As is noted in the aforenoted co-pending
applications, certain of the steps which will be described can be
performed while the mounting head 28 is moving either the pick up
position and/or to the position where the component will be
mounted. Said another way, the only portion of the control routine
which will be described is the control routine wherein the
component or components are picked up, recognized, the correction
calculation made and the mounting calculations made. Those skilled
in the art can readily understand how these procedures can be
interfaced with the procedure for moving the head assembly 28 to
the pick up and mounting locations and to the external photographic
recognition station 58.
Referring now to the embodiment of FIG. 11, this is the control
routine which is employed when a component such as the component
C.sub.1 which is recognized by the camera 58 is picked up and
mounted. Hence, the block diagram of FIG. 11 will relate to FIGS. 4
and 5 of the drawings which show this type of recognition
situation.
After the program is stated, the axis driver control 85 energizes
both Z axis servo motors 45 and 46 to raise both the nozzles 43 and
44 to a fully retracted position where they will be clear of the
photo assist device 59. This is the position shown in FIG. 8.
The program moves to the step S-2 to determine if these nozzles
have then been out of interference range with the photo assist
device 59. This may be either be done by measuring their height
position from the Z axis position detectors 47 and 52 or by means
of some form of limit switch or interference sensor. If the device
is not out of the interference range, the program moves back to the
step S-1 so as to continue the elevation.
If, however, at the step S-2 it has been determined both of the
nozzles 43 and 44 are out of interference position with the photo
assist device 59, the program at the step S-3 operates to actuate
the cylinder 65 so as to move the photo assist device 59 to the
position shown in FIGS. 4 and 5 wherein the opening 63 registers
with the nozzle 43.
The program then moves to the step S-4 to determine if the photo
assist device 59 is in this first position. If it is not, the
program repeats.
If, however, it is determined at the step S-4 that the photo assist
device 59 is in its first position, then the program moves to the
step S-5 so as to move the head unit 28 to the attracting position
in registry with the appropriate feeder section 25 or 26 to pick up
the appropriate component. The program then moves to the step S-6
so as to lower only the pick up nozzle 43 toward the component to
be picked up. This is done by actuating the Z axis servo motor
45.
The program then moves to the step S-7 wherein the correct
component C.sub.1 is attracted by exerting vacuum on the nozzle 43.
The program then moves to the step S-8 so as to raise the pick-up
nozzle 43 to a position wherein the nozzle 43 (or component
C.sub.1) will be positioned below the photo assist device 59.
The program then moves to the step S-9 so as to move the mounting
head assembly 28 to a position over the component camera 58 at one
side of the conveyor 24.
Once the component is disposed above the component camera 58, the
program moves to the step S-10 so as to illuminate the LED's 61 of
the photo assist device 59 and then actuate the camera 58 at the
step S-11 so as to take the picture.
This picture is then transmitted to the image processing section 83
at the step S-12 and the shape of the component as photographed is
compared with the photographs in the memory so as to determine that
the correct component has been picked up and, at the same time, the
deviations in the position of the component relative to the pick-up
nozzle 43 both around the rotational axis R and in the X and Y
planes are also determined.
These establish correction factors that are then programmed into
the main processor 84 so as to move the head 28 to the appropriate
mounting position at the step S-13 and mount the component at this
time.
Referring now to the routine of FIG. 12, this shows the control
routine where one or more components that can be recognized in the
optical detector unit 54 are picked up by the nozzles 43 and/or 44.
This configuration is depicted in FIGS. 6 and 7 wherein components
C.sub.2 are picked up by both of the nozzles 43 and 44. It should
be understood that this routine can be used regardless of whether
one or two components are picked up.
When the program starts, it moves to the step S-21 wherein the axis
driver controller 85 actuates both Z axis servo motors 45 and 46 of
the pick-up nozzles 43 and 44 so as to elevate these pick-up
nozzles. The program then moves to the step S-22 to determine that
the pick-up nozzles are raised to a position where they will be
free of interference with the photo assist unit 59. It should be
noted that prior to this operation, the photo assist device 59
could have been in the position of FIGS. 4 and 5 at the completion
of the previous routine of FIG. 11. If the nozzles 43 and 44 are
not free of the photo assist unit 59, the program repeats. Again,
this can be determined either by the output of the Z axis position
detectors 47 and 48 or by means of a separate interference
detector.
If at the step S-22 it is determined that the nozzles 43 and 44 are
free of interference with the photo assist device, then at the step
S-23 the cylinder 65 is actuated to move the device to the second
position as shown in FIGS. 6 and 7. It is determined then at the
step S-24 whether the photo assist device 59 is clear. If it is
not, the program repeats.
If it is determined at the step S-24 that the photo assist device
59 is in its second position, then the program moves the step S-25
so as to attract the component or components by lowering the
respective pick-up nozzles 43 and/or 44 when they are appropriately
positioned over the respective tape feeder 25 or 26.
The components then picked up are recognized simultaneously within
the detecting section 54 at the step S-26 in the manner described
in co-pending application Ser. No. 86,512. This also determines the
corrective factor of the X and Y axes and the rotational corrective
factor around the R axis. The components are then mounted at the
step S-27.
The final control routine of the mounting head 28 will now be
described by reference to FIG. 13 and this is the control routine
when the mounting head 28 and specifically the substrate or circuit
board camera 76 is employed.
The program starts and moves to the step S-31 so as to move the
mounting head 28 to an area above the conveyor 24 and specifically
a substrate 27 positioned thereon in a location where the
recognition mark of the substrate is positioned. Again, this is
done by operating the X and Y axis servo motors 35 and 39.
The program then moves to the step S-32 so as to raise both pick-up
nozzles 43 and 44 to a position where they are free of interference
with the photo assist unit 59, this being the position shown in
FIGS. 8 and 9. When the elevation is started, the program moves to
the step S-33 to determine if the photo assist unit 59 is free of
interference with the nozzles 43 and 44. If they are not, the
program repeats. Again, this can be done either by the outputs from
the Z axis position detectors 47 and 48 or by a separate
interference detector.
The program then moves to the step S-34 so as to move the photo
assist 59 to the position shown in FIG. 8 by actuating only the
cylinder 73. The program then moves to the step S-35 to insure that
this movement is completed. If it is not, the program repeats.
If, however, at the step S-35 it is determined that the photo
assist device is in the position shown in FIG. 8, then the program
moves to the step S-36 so as to turn on the LED's 61 and at the
step S-37 to photograph the substrate or circuit board by actuating
the camera 76.
The image thus produced is then compared at the step S-38 in the
image processing section 83 with those memorized and the main
processor 84 then determines the recognition of the substrate and
the program ends.
In the described series of operations of FIGS. 11 through 13, a
certain sequence of operation has been assumed. It is to be
understood that certain steps in the sequence may be interposed
with each other. For example, the led unit may be turned on at
another time. Also, these steps or some of them may take place when
the head 28 is actually being moved, again depending upon the
control routine followed.
It should be readily apparent from the foregoing description that
the described apparatus is capable of performing and satisfying the
objects as aforenoted in extremely simple and yet highly effective
manner. Of course, the foregoing description is that only of
preferred embodiments of the invention and various changes and
modifications may be made without departing from the spirit and
scope of the invention, as defined by the appended claims.
* * * * *